Color Temperature Mired Shift Calculator

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Audio, Music, Photography & Color

Tranche

tranche-7

Evidence ID

t7-050

Ledger rows

1

No ledger note is attached.

Review findings

The reciprocal-temperature arithmetic is correct, but the instrument cannot honestly promise manufacturer-specific gel identification or stop-loss output until the exact lookup-table source, product convention, sign convention, and transmission-loss data are specified. The current honest_label field is empty and should state that gel names and stop losses are nominal or manufacturer-specific.

Formula and scope findings

• The core formula mired = 10^6/K is standard when K is an absolute color temperature in kelvin, and adding a signed mired shift is standard.
• The sign convention is unspecified: a warmer correction such as CTO normally has a positive mired shift, while a cooler correction such as CTB normally has a negative mired shift.
• For target-temperature mode, the specification should explicitly define shift = (10^6/target_K) - (10^6/source_K).
• The gel lookup values are nominal and manufacturer-dependent; the specification does not identify a particular Rosco or Lee product line, edition, or exact table.
• Suggested gel stops cannot be computed from mired shift alone. Transmission, density, and stop-loss data for the specific gel manufacturer and product are required.

Unit assumptions

• All color-temperature inputs and outputs are in kelvin (K), not degrees Celsius.
• Mired values and gel shifts are in reciprocal megakelvin (MK^-1), conventionally called mired; numerically mired = 10^6/K.
• A positive signed shift increases the mired value and lowers the resulting Kelvin temperature.
• A negative signed shift decreases the mired value and raises the resulting Kelvin temperature.
• The nominal gel table values used here are manufacturer-chart conventions: Full CTO +159, 1/2 CTO +81, 1/4 CTO +41, 1/8 CTO +20, Full CTB -131, 1/2 CTB -81, 1/4 CTB -40, and 1/8 CTB -20 mired.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

The formula reaches an undefined division-by-zero result when the applied shift makes resulting mired equal zero. The specification also leaves the sign convention and manufacturer gel lookup data insufficiently defined, allowing materially different outputs or missing gel recommendations.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "source_temperature_K": 6500,
    "gel_shift_mired": 159
  },
  "expected_outputs": {
    "source_mired": 153.8461538462,
    "resulting_mired": 312.8461538462,
    "resulting_temperature_K": 3196.459,
    "suggested_gel": "Full CTO",
    "suggested_gel_shift_mired": 159,
    "stop_loss": "unavailable from mired shift alone"
  },
  "reference_data": {
    "source_temperature_mired": {
      "temperature_K": 6500,
      "mired": 153.8461538462,
      "source_convention": "widely tabulated standard color-temperature value"
    },
    "gel_row": {
      "gel": "Full CTO",
      "mired_shift": 159,
      "source_convention": "widely tabulated standard value from common Rosco/Lee CTO mired-shift charts"
    }
  },
  "working": "source mired = 1,000,000 / 6500 = 153.8461538462 mired; resulting mired = 153.8461538462 + 159 = 312.8461538462 mired; resulting K = 1,000,000 / 312.8461538462 = 3196.459 K; the +159 lookup row corresponds to Full CTO."
}

Related workflows

No source-defined multi-instrument workflow membership is recorded.

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche7/tranche7-results.json
• BOUNDARY_HAZARD_CATALOG.json